Hazmat workers with Protect Environmental unload barrels in preparation for decontaminating an apartment at The Village Bend East apartment complex where a second health-care worker who has tested positive for the Ebola virus resides on Oct 15, 2014 in Dallas, Texas. The newest case of nurse Amber Vinson joins nurse Nina Pham, who also contracted the Ebola virus at Texas Heath Presbyterian Hospital while treating patient Thomas Eric Duncan, who has since died. -- PHOTO: AFP

The Ohio Health Department was racing to trace contacts of a second Texas nurse diagnosed with Ebola who flew from Cleveland to Dallas one day before she tested positive for the virus, as city officials here said they immediately activated an "emergency command centre" after being informed of the woman's visit.

Cleveland Department of Public Health director Toinette Parrilla told a news conference that her department has an emergency response plan and that she had called up all its appropriate team members. They have very specific roles for "situation awareness so that we are in constant communication, that we have up-to-date information, to protect all of our Clevelanders and all of our visitors", she said.

The victim - the second nurse to have been stricken with the deadly virus after treating Liberian patient Thomas Eric Duncan in Dallas - was identified to Reuters by her grandmother as Amber Vinson, 29. She was isolated immediately after reporting a fever on Tuesday, Texas Department of State Health Services officials said.

"She flew into Cleveland to prepare for her wedding, visiting her mother and her mother's fiancee while here. She departed from Cleveland Hopkins on Monday the 13th (Oct) and arrived in Dallas that afternoon," Parrilla said before being cut off by another woman present at the conference from giving further information on Vinson.

Earlier Cleveland Mayor Frank Jackson assured residents that there were no known cases of Ebola in the city itself at present.

The Cleveland Plain Dealer newspaper earlier tweeted that Vinson had visited nearby Kent State University during her trip to the area, but officials there later back-tracked on that report. The university, noted in song and American history for the fatal shooting of four students during anti-Vietnam War riots on May 4, 1970, has a student population of nearly 23,000.

Ohio's health department said it was working with airline officials to track down additional people Vinson may have come into contact with, Reuters reported its spokesman Jay Carey as saying. It is waiting on additional instructions from the US Centres for Disease Control and Prevention (CDC) and Texas Health Department, he added.

But the latest revelation raised disturbing questions about the handling of Duncan's case and its aftermath by both the hospital in Texas and the CDC.

Earlier, CDC Director Dr. Thomas Frieden told reporters Vinson should not have been travelled on a plane.

"The patient had travelled to Ohio before it was known that the first healthcare worker was ill. At that point that patient as well as the rest of the healthcare team were undergoing self-monitoring," he said. "The second healthcare worker reported no symptoms and no fever. However, because at that point she was in a group of individuals known to have exposure to Ebola, she should not have travelled on a commercial flight."

The agency said earlier that it was asking all of the more than 130 passengers who shared the Oct 13 flight with Vinson - Frontier Airlines flight 1143 from Cleveland to Dallas/Fort Worth - to contact the CDC at 1 800 CDC-INFO (1 800 232-4636)."

Concerns over Ebola have rattled US markets, with the Dow Jones Industrial Average down 2.5 per cent on Wednesday.

The Straits Times

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